Command 0x90 (144): Get Motor M0 Current
Compact protocol: 0x90
Pololu protocol: 0xAA, device ID, 0x10
Command 0x91 (145): Get Motor M1 Current
Compact protocol: 0x91
Pololu protocol: 0xAA, device ID, 0x11
These commands return 8-bit representations of the average motor currents over the last 5 ms. To convert the returned value to an approximate current, multiply it by 150 mA. Please note that the actual current could differ from this value by as much as 20%, so you might consider empirically characterizing the current feedback from each motor driver to obtain a more accurate relationship between the values returned by this command and the actual driver output current.